Validation of a simple model for predicting liver fibrosis in HIV/hepatitis C virus-coinfected patients

Insights Into the Coinfections of Human Immunodeficiency Virus-Hepatitis B Virus, Human Immunodeficiency Virus-Hepatitis C Virus, and Hepatitis B Virus-Hepatitis C Virus: Prevalence, Risk Factors, Pathogenesis, Diagnosis, and Treatment

Human immunodeficiency virus, hepatitis B virus, and hepatitis C virus are three blood-borne viruses that can cause major global health issues by increasing severe morbidity. There is a high risk of coinfection with these viruses in individuals because of their same transmission routes through blood using shared needles, syringes, other injection equipment, sexual transmission, or even vertical transmission. Coinfection can cause various liver-related illnesses, non-hepatic organ dysfunction, followed by death compared to any of these single infections. The treatment of coinfected patients is complicated due to the side effects of antiviral medication, resulting in drug resistance, hepatotoxicity, and a lack of required responses. On the other hand, coinfected individuals must be treated with multiple drugs simultaneously, such as for HIV either along with HBV or HCV and HBV and HCV. Therefore, diagnosing, treating, and controlling dual infections with HIV, HBV, or HCV is complicated and needs further investigation. This review focuses on the current prevalence, risk factors, and pathogenesis of dual infections with HIV, HBV, and HCV. We also briefly overviewed the diagnosis and treatment of coinfections of these three blood-borne viruses.

Clinical and demographic predictors of antiretroviral efficacy in HIV-HBV co-infected patients

BACKGROUND

The clinical and demographic characteristics that predict antiretroviral efficacy among patients co-infected with HIV and hepatitis B virus (HBV) remain poorly defined. We evaluated HIV virological suppression and rebound in a cohort of HIV-HBV co-infected patients initiated on antiretroviral therapy.

METHODS

A retrospective cohort analysis was performed with Canadian Observation Cohort Collaboration data. Cox proportional hazards models were used to determine the factors associated with time to virological suppression and time to virological rebound.

RESULTS

HBV status was available for 2,419 participants. A total of 8% were HBV co-infected, of whom 95% achieved virological suppression. After virological suppression, 29% of HIV-HBV co-infected participants experienced HIV virological rebound. HBV co-infection itself did not predict virological suppression or rebound risk. The rate of virological suppression was lower among patients with a history of injection drug use or baseline CD4 cell counts of <199 cells per cubic millimetre. Low baseline HIV RNA and men-who-have-sex-with-men status were significantly associated with a higher rate of virological suppression. Injection drug use and non-White race predicted viral rebound.

CONCLUSIONS

HBV co-infected HIV patients achieve similar antiretroviral outcomes as those living with HIV mono-infection. Equitable treatment outcomes may be approached by targeting resources to key subpopulations living with HIV-HBV co-infection.

Distinct Hepatitis B and HIV co-infected populations in Canada

Due to shared modes of exposure, HIV-HBV co-infection is common worldwide. Increased knowledge of the demographic and clinical characteristics of the co-infected population will allow us to optimize our approach to management of both infections in clinical practice. The Canadian Hepatitis B Network Cohort was utilized to conduct a cross-sectional evaluation of the demographic, biochemical, fibrotic and treatment characteristics of HIV-HBV patients and a comparator HBV group. From a total of 5996 HBV-infected patients, 335 HIV-HBV patients were identified. HIV-HBV patients were characterized by older median age, higher male and lower Asian proportion, more advanced fibrosis and higher anti-HBV therapy use (91% vs. 30%) than the HBV-positive / HIV seronegative comparator group. A history of reported high-risk exposure activities (drug use, high-risk sexual contact) was more common in HIV-HBV patients. HIV-HBV patients with reported high-risk exposure activities had higher male proportion, more Caucasian ethnicity and higher prevalence of cirrhosis than HIV-HBV patients born in an endemic country. In the main cohort, age ≥60 years, male sex, elevated ALT, the presence of comorbidity and HCV seropositivity were independent predictors of significant fibrosis. HIV seropositivity was not an independent predictor of advanced fibrosis (adj OR 0.75 [95%CI: 0.34-1.67]). In conclusion, Canadian co-infected patients differed considerably from those with mono-infection. Furthermore, HIV-HBV-infected patients who report high-risk behaviours and those born in endemic countries represent two distinct subpopulations, which should be considered when engaging these patients in care.

Demographic and clinical factors associated with immune reconstitution in HIV/HBV co-infected and HIV mono-infected patients: a retrospective cohort study

OBJECTIVES

To describe the clinical characteristics and factors associated with CD4 T-cell count and CD4/CD8 ratio restoration in HIV mono-infected and HIV/HBV co-infected individuals, and to explore liver and renal functional changes in both groups.

METHODS

A retrospective cohort study was performed including 356 HIV/HBV co-infected and 716 HIV mono-infected participants who initiated antiretroviral therapy (ART) during 2013-2017 in Beijing Youan Hospital, China. Demographic and clinical characteristics were compared between the two groups, using χ² and Mann-Whitney non-parametric tests. Bivariate and multivariate Cox regression models were used to test their association.

RESULTS

Baseline HIV viral load and ART regimen were found to be significantly associated with CD4 T-cell restoration among HIV-infected participants, whereas baseline HIV viral load was the only significant factor associated with CD4 T-cell restoration in HIV/HBV co-infected participants. The final model showed that baseline HIV viral load and ART regimen were significantly associated with CD4/CD8 ratio restoration among HIV-infected participants, while baseline HIV viral load was the significant factor. Liver and renal functions were similar at the endpoint (P > 0.05).

CONCLUSIONS

Baseline HIV viral load count was found to be the key factor affecting immune restoration in both HIV and HIV/HBV individuals. Future multi-wave prospective studies are needed to clarify the potential biological mechanism.

Characteristics and outcomes of antiretroviral-treated HIV-HBV co-infected patients in Canada?

BACKGROUND

Hepatitis B (HBV) and Human Immunodeficiency Virus (HIV) share common risk factors for exposure. Co-infected patients have an increased liver-related mortality risk and may have accelerated HIV progression. The epidemiology and demographic characteristics of HIV-HBV co-infection in Canada remain poorly defined. We compared the demographic and clinical characteristics and factors associated with advanced hepatic fibrosis between HIV and HIV-HBV co-infected patients.

METHODS

A retrospective cohort analysis was conducted using data from the Canadian Observational Cohort (CANOC) Collaboration, including eight sites from British Columbia, Quebec, and Ontario. Eligible participants were HIV-infected patients who initiated combination ARV between January 1, 2000 and December 14, 2014. Demographic and clinical characteristics were compared between HIV-HBV co-infected and HIV-infected groups using chi-square or Fisher exact tests for categorical variables, and Wilcoxon's Rank Sum test for continuous variables. Liver fibrosis was estimated by the AST to Platelet Ratio Index (APRI).

RESULTS

HBV status and APRI values were available for 2419 cohort participants. 199 (8%) were HBV co-infected. Compared to HIV-infected participants, HIV-HBV co-infected participants were more likely to use injection drugs (28% vs. 21%, p = 0.03) and be HCV-positive (31%, vs. 23%, p = 0.02). HIV-HBV co-infected participants had lower baseline CD4 T cell counts (188 cells/mm3, IQR: 120-360) compared to 235 cells/mm3 in HIV-infected participants (IQR: 85-294) (p = 0.0002) and higher baseline median APRI scores (0.50 vs. 0.37, p < 0.0001). This difference in APRI was no longer clinically significant at follow-up (0.32 vs. 0.30, p = 0.03). HIV-HBV co-infected participants had a higher mortality rate compared to HIV-infected participants (11% vs. 7%, p = 0.02).

CONCLUSION

The prevalence, demographic and clinical characteristics of the HIV-HBV co-infected population in Canada is described. HIV-HBV co-infected patients have higher mortality, more advanced CD4 T cell depletion, and liver fibrosis that improves in conjunction with ARV therapy. The high prevalence of unknown HBV status demonstrates a need for increased screening among HIV-infected patients in Canada.

Clinical significance of elevated liver transaminases in HIV-infected patients

: Elevation of liver transaminases is common in patients infected with the HIV. Although this is usually an incidental finding during regular work-up, HIV-infected patients with transaminase elevations require additional visits for laboratory studies and clinical assessments, and often undergo interruptions and changes in antiretroviral therapy (ART). Alanine aminotransferase is present primarily in the liver, thus being a surrogate marker of hepatocellular injury. Aspartate aminotransferase is present in the liver and other organs, namely cardiac and skeletal muscle, kidney and brain. Serum levels of both liver transaminases predict liver-related mortality. Moreover, serum fibrosis biomarkers based on alanine aminotransferase and aspartate aminotransferase predict all-cause mortality. In a busy clinical setting, a diagnostic approach to elevated liver transaminases could be complicated given the frequency and nonspecificity of this finding. Indeed, HIV-infected individuals present multiple risk factors for liver damage and chronic elevation of transaminases, including coinfection with hepatitis B and C viruses, alcohol abuse, hepatotoxicity due to ART, HIV itself and frequent metabolic comorbidities leading to nonalcoholic fatty liver disease. This review provides an update on epidemiology of elevated liver transaminases, summarizes the main etiologic contributors and discusses the prognostic significance and a pragmatic approach to this frequent finding in the clinical practice of HIV medicine. With the aging of the HIV-infected population following the successful implementation of ART in Western countries, liver-related conditions are now a major comorbidity in this setting. As such, clinicians should be aware of the frequency, clinical significance and diagnostic approach to elevated liver transaminases.

Reproductive Aging and Hepatic Fibrosis Progression in Human Immunodeficiency Virus/Hepatitis C Virus-Coinfected Women

BACKGROUND

Severity of hepatic fibrosis is greater in postmenopausal than in premenopausal women, perhaps owing to protective effects of estrogens. However, prior studies of estrogen and liver fibrosis lack serial fibrosis measures, adjustment for age, or longitudinal observations in coinfected populations.

METHODS

In a longitudinal cohort of women coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV), we assessed fibrosis progression across reproductive age, using validated serum fibrosis markers, aminotransferase platelet ratio index (APRI) and fibrosis 4 (FIB-4). Fibrosis rate was evaluated within each woman as she transitioned from pre- to postmenopause, defined by a biomarker of ovarian function.

RESULTS

The median follow-up (n = 405) was 9.1 years (interquartile range, 5.0-15.2 years), with a median menopausal age of 49 years (47-52 years). When fully controlled for chronologic aging, the fibrosis progression rate was accelerated during perimenopause, as shown using FIB-4 (0.12 units per year faster than during premenopause; 95% confidence interval [CI], .02-.21; P = .01) and APRI (0.05 units per year faster; -.002 to .09; P = .06). Accelerated fibrosis was also observed during postmenopause compared with premenopause, for FIB-4 (0.14 units per year faster; 95% CI, -.01 to .29; P = .07) and APRI (0.07 units per year faster; -.003 to .15; P = .06). Accelerated fibrosis in perimenopause persisted after adjustment for Hispanic ethnicity, antiretroviral use, and alcohol (0.10 FIB-4 units per year faster than during premenopause; 95% CI, .008-.20; P = .03).

CONCLUSIONS

In HIV/HCV-coinfected women, hepatic fibrosis accelerates with reproductive aging. Accelerated fibrosis begins in perimenopause, highlighting a previously unrecognized group of women at increased risk for advanced fibrosis and associated complications. Longitudinal analyses of fibrosis rates across reproductive age should be conducted in non-HCV-related liver diseases, given potential implications in a broader spectrum of women.

A prognostic model for development of significant liver fibrosis in HIV-hepatitis C co-infection

BACKGROUND

Liver fibrosis progresses rapidly in HIV-Hepatitis C virus (HCV) co-infected individuals partially due to heightened inflammation. Immune markers targeting stages of fibrogenesis could aid in prognosis of fibrosis.

METHODS

A case-cohort study was nested in the prospective Canadian Co-infection Cohort (n = 1119). HCV RNA positive individuals without fibrosis, end-stage liver disease or chronic Hepatitis B at baseline (n = 679) were eligible. A random subcohort (n = 236) was selected from those eligible. Pro-fibrogenic markers and Interferon Lambda (IFNL) rs8099917 genotype were measured from first available sample in all fibrosis cases (APRI ≥ 1.5 during follow-up) and the subcohort. We used Cox proportional hazards and compared Model 1 (selected clinical predictors only) to Model 2 (Model 1 plus selected markers) for predicting 3-year risk of liver fibrosis using weighted Harrell's C and Net Reclassification Improvement indices.

RESULTS

113 individuals developed significant liver fibrosis over 1300 person-years (8.63 per 100 person-years 95% CI: 7.08, 10.60). Model 1 (age, sex, current alcohol use, HIV RNA, baseline APRI, HCV genotype) was nested in model 2, which also included IFNL genotype and IL-8, sICAM-1, RANTES, hsCRP, and sCD14. The C indexes (95% CI) for model 1 vs. model 2 were 0.720 (0.649, 0.791) and 0.756 (0.688, 0.825), respectively. Model 2 classified risk more appropriately (overall net reclassification improvement, p<0.05).

CONCLUSIONS

Including IFNL genotype and inflammatory markers IL-8, sICAM-1, RANTES, hs-CRP, and sCD14 enabled better prediction of the 3-year risk of significant liver fibrosis over clinical predictors alone. Whether this modest improvement in prediction justifies their additional cost requires further cost-benefit analyses.

Cocaine/crack use is not associated with fibrosis progression measured by AST-to-Platelet Ratio Index in HIV-HCV co-infected patients: a cohort study

Background

Cocaine and crack use has been associated with HIV and HCV infections, but its consequences on HCV progression have not been well established. We analyzed the impact of cocaine/crack use on liver fibrosis progression in a cohort of HIV-HCV co-infected patients.

Methods

A Canadian multicenter prospective cohort study followed 1238 HIV-HCV co-infected persons every 6 months between 2003 and 2013. Data were analyzed from 573 patients with positive HCV RNA, not on HCV treatment, without significant liver fibrosis (AST-to-Platelet Ratio Index (APRI) <1.5) or history of end-stage liver disease at baseline, and having at least two study visits. Recent cocaine/crack use was defined as use within 6 months of cohort entry. Incidence rates of progression to significant fibrosis (APRI ≥ 1.5) were determined according to recent cocaine/crack use. Cox Proportional Hazards models were used to assess the association between time-updated cocaine/crack use and progression to APRI ≥ 1.5 adjusting for age, sex, HCV duration, baseline ln(APRI), and time-updated alcohol abuse, history of other drug use and CD4+ cell count.

Results

At baseline, 211 persons (37%) were recent cocaine/crack users and 501 (87%) ever used cocaine/crack. Recent users did not differ from non-recent users on gender, age, and CD4+ T-cell count. Over 1599 person-years of follow up (522 PY in recent users, 887 PY in previous users and 190 PY in never users),158 (28%) persons developed significant fibrosis (9.9/100 PY; 95% CI, 8.3–11.4); 56 (27%) recent users (10.7/100 PY; 7.9–13.5), 81 (28%) previous users (9.1/100 PY; 7.1–11.1), and 21 (29%) never users (11.1/100 PY; 6.3–15.8). There was no association between ever having used or time-updated cocaine/crack use and progression to APRI ≥ 1.5 (adjusted HR (95%CI): 0.96 (0.58, 1.57) and 0.88;(0.63–1.25), respectively).

Conclusions

We could not find evidence that cocaine/crack use is associated with progression to advanced liver fibrosis in our prospective study of HIV-HCV co-infected patients.

Diagnostic accuracy of APRI and FIB-4 for predicting hepatitis B virus-related liver fibrosis accompanied with hepatocellular carcinoma

BACKGROUND

Aspartate aminotransferase to platelet ratio index (APRI) and the fibrosis index based on four factors (FIB-4) are the two most focused non-invasive models to assess liver fibrosis.

AIMS

We aimed to examine the validity of these two models for predicting hepatitis B virus (HBV)-related liver fibrosis accompanied with hepatocellular carcinoma (HCC).

METHODS

We enrolled HBV-infected patients with liver cancer who had received hepatectomy. The accuracy of APRI and FIB-4 for diagnosing liver fibrosis was assessed based on their sensitivity, specificity, diagnostic efficiency, positive predictive value (PPV), negative predictive value (NPV), kappa (κ) value and area under the receiver-operating characteristic curve (AUC).

RESULTS

Finally 2176 patients were included, with 1682 retrospective subjects and 494 prospective subjects. APRI (rs=0.310) and FIB-4 (rs=0.278) were positively correlated with liver fibrosis. And χ(2) analysis demonstrated that APRI and FIB-4 values correlated with different levels of liver fibrosis with all P values less than 0.01. The AUC values for APRI and FIB-4 were 0.685 and 0.626 (P=0.73) for predicting significant fibrosis, 0.681 and 0.648 (P=0.81) for differentiation of advanced fibrosis and 0.676 and 0.652 (P=0.77) for diagnosing cirrhosis.

CONCLUSION

APRI and FIB-4 correlate with liver fibrosis. However these two models have low accuracy for predicting HBV-related liver fibrosis in HCC patients.

Correcting for Measurement Error in Time-Varying Covariates in Marginal Structural Models

Unbiased estimation of causal parameters from marginal structural models (MSMs) requires a fundamental assumption of no unmeasured confounding. Unfortunately, the time-varying covariates used to obtain inverse probability weights are often error-prone. Although substantial measurement error in important confounders is known to undermine control of confounders in conventional unweighted regression models, this issue has received comparatively limited attention in the MSM literature. Here we propose a novel application of the simulation-extrapolation (SIMEX) procedure to address measurement error in time-varying covariates, and we compare 2 approaches. The direct approach to SIMEX-based correction targets outcome model parameters, while the indirect approach corrects the weights estimated using the exposure model. We assess the performance of the proposed methods in simulations under different clinically plausible assumptions. The simulations demonstrate that measurement errors in time-dependent covariates may induce substantial bias in MSM estimators of causal effects of time-varying exposures, and that both proposed SIMEX approaches yield practically unbiased estimates in scenarios featuring low-to-moderate degrees of error. We illustrate the proposed approach in a simple analysis of the relationship between sustained virological response and liver fibrosis progression among persons infected with hepatitis C virus, while accounting for measurement error in γ-glutamyltransferase, using data collected in the Canadian Co-infection Cohort Study from 2003 to 2014.

CIHR Canadian HIV Trials Network Coinfection and Concurrent Diseases Core Research Group: 2016 Updated Canadian HIV/Hepatitis C Adult Guidelines for Management and Treatment

Background. Hepatitis C virus (HCV) coinfection occurs in 20-30% of Canadians living with HIV and is responsible for a heavy burden of morbidity and mortality. Purpose. To update national standards for management of HCV-HIV coinfected adults in the Canadian context with evolving evidence for and accessibility of effective and tolerable DAA therapies. The document addresses patient workup and treatment preparation, antiviral recommendations overall and in specific populations, and drug-drug interactions. Methods. A standing working group with HIV-HCV expertise was convened by The Canadian Institute of Health Research HIV Trials Network to review recently published HCV antiviral data and update Canadian HIV-HCV Coinfection Guidelines. Results. The gap in sustained virologic response between HCV monoinfection and HIV-HCV coinfection has been eliminated with newer HCV antiviral regimens. All coinfected individuals should be assessed for interferon-free, Direct Acting Antiviral HCV therapy. Regimens vary in content, duration, and success based largely on genotype. Reimbursement restrictions forcing the use of pegylated interferon is not acceptable if optimal patient care is to be provided. Discussion. Recommendations may not supersede individual clinical judgement. Treatment advances published since December 2015 are not considered in this document.

Responder Interferon λ Genotypes Are Associated With Higher Risk of Liver Fibrosis in HIV-Hepatitis C Virus Coinfection

Background. Liver fibrosis progresses faster in individuals coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). Interferon λ3 (IFN-λ3) has both antiviral and proinflammatory properties. Genotypes at IFNL single-nucleotide proteins (SNPs; rs12979860CC and rs8099917TT) are linked to higher HCV clearance, potentially via rs8103142. We examined the relationship between IFN-λ genotypes and significant liver fibrosis in HIV-HCV coinfection.

Methods. From the prospective Canadian Co-infection Cohort (n = 1423), HCV RNA–positive participants in whom IFN-λ genotypes were detected and who were free of fibrosis, end-stage liver disease, and chronic hepatitis B at baseline (n = 485) were included. Time to significant fibrosis (defined as an aspartate transaminase level to platelet count ratio index [APRI] of ≥1.5) by IFN-λ genotypes was analyzed using Cox proportional hazards, with adjustment for age, sex, ethnicity, alcohol use, CD4⁺ T-cell count, HCV genotype, γ-glutamyl transferase level, and baseline APRI. Haplotype analysis was performed, with adjustment for ethnicity.

Results. A total of 125 participants developed fibrosis over 1595 person-years (7.84 cases/100 person-years; 95% confidence interval [CI], 6.58–9.34 cases/100 person-years). Each genotype was associated with an increased fibrosis risk, with adjusted hazard ratios of 1.37 (95% CI, .94–2.02) for rs12979860CC, 1.34 (95% CI, .91–1.97) for rs8103142TT, and 1.79 (95% CI, 1.24–2.57) for rs8099917TT. Haplotype TCT was also linked with a higher risk (hazard ratio, 1.14 [95% CI, .73–1.77]).

Conclusions. IFN-λ SNPs rs12979860, rs8099917, and rs81013142 were individually linked to higher rates of fibrosis in individuals with HIV-HCV coinfection. IFN-λ genotypes may be useful to target HCV treatments to people who are at higher risk of liver disease.

Tobacco Smoking Is Not Associated With Accelerated Liver Disease in Human Immunodeficiency Virus-Hepatitis C Coinfection: A Longitudinal Cohort Analysis

Background. Tobacco smoking has been shown to be an independent risk factor for liver fibrosis in hepatitis C virus (HCV) infection in some cross-sectional studies. No longitudinal study has confirmed this relationship, and the effect of tobacco exposure on liver fibrosis in human immunodeficiency virus (HIV)-HCV coinfected individuals is unknown.

Methods. The study population consisted of participants from the Canadian Co-infection Cohort study (CTN 222), a multicenter longitudinal study of HIV-HCV coinfected individuals from 2003 to 2014. Data were analyzed for all participants who did not have significant fibrosis or end-stage liver disease (ESLD) at baseline. The association between time-updated tobacco exposure (ever vs nonsmokers and pack-years) and progression to significant liver fibrosis (defined as an aspartate-to-platelet ratio index [APRI] ≥1.5) or ESLD was assessed by pooled logistic regression.

Results. Of 1072 participants included in the study, 978 (91%) had ever smoked, 817 (76%) were current smokers, and 161 (15%) were previous smokers. Tobacco exposure was not associated with accelerated progression to significant liver fibrosis nor with ESLD when comparing ever vs never smokers (odds ratio [OR] = 1.06, 95% confidence interval [CI], 0.43–1.69 and OR = 1.20, 95% CI, 0.21–2.18, respectively) or increases in pack-years smoked (OR = 1.05, 95% CI, 0.97–1.14 and OR = 0.94, 95% CI, 0.83–1.05, respectively). Both time-updated alcohol use in the previous 6 months and presence of detectable HCV ribonucleic acid were associated with APRI score ≥1.5.

Conclusions. Tobacco exposure does not appear to be associated with accelerated progression of liver disease in this prospective study of HIV-HCV coinfected individuals.

The Impact of Sparse Follow-up on Marginal Structural Models for Time-to-Event Data

The impact of risk factors on the amount of time taken to reach an endpoint is a common parameter of interest. Hazard ratios are often estimated using a discrete-time approximation, which works well when the by-interval event rate is low. However, if the intervals are made more frequent than the observation times, missing values will arise. We investigated common analytical approaches, including available-case (AC) analysis, last observation carried forward (LOCF), and multiple imputation (MI), in a setting where time-dependent covariates also act as mediators. We generated complete data to obtain monthly information for all individuals, and from the complete data, we selected "observed" data by assuming that follow-up visits occurred every 6 months. MI proved superior to LOCF and AC analyses when only data on confounding variables were missing; AC analysis also performed well when data for additional variables were missing completely at random. We applied the 3 approaches to data from the Canadian HIV-Hepatitis C Co-infection Cohort Study (2003-2014) to estimate the association of alcohol abuse with liver fibrosis. The AC and LOCF estimates were larger but less precise than those obtained from the analysis that employed MI.

Cost-effectiveness of non-invasive methods for assessment and monitoring of liver fibrosis and cirrhosis in patients with chronic liver disease: systematic review and economic evaluation

BACKGROUND

Liver biopsy is the reference standard for diagnosing the extent of fibrosis in chronic liver disease; however, it is invasive, with the potential for serious complications. Alternatives to biopsy include non-invasive liver tests (NILTs); however, the cost-effectiveness of these needs to be established.

OBJECTIVE

To assess the diagnostic accuracy and cost-effectiveness of NILTs in patients with chronic liver disease.

DATA SOURCES

We searched various databases from 1998 to April 2012, recent conference proceedings and reference lists.

METHODS

We included studies that assessed the diagnostic accuracy of NILTs using liver biopsy as the reference standard. Diagnostic studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Meta-analysis was conducted using the bivariate random-effects model with correlation between sensitivity and specificity (whenever possible). Decision models were used to evaluate the cost-effectiveness of the NILTs. Expected costs were estimated using a NHS perspective and health outcomes were measured as quality-adjusted life-years (QALYs). Markov models were developed to estimate long-term costs and QALYs following testing, and antiviral treatment where indicated, for chronic hepatitis B (HBV) and chronic hepatitis C (HCV). NILTs were compared with each other, sequential testing strategies, biopsy and strategies including no testing. For alcoholic liver disease (ALD), we assessed the cost-effectiveness of NILTs in the context of potentially increasing abstinence from alcohol. Owing to a lack of data and treatments specifically for fibrosis in patients with non-alcoholic fatty liver disease (NAFLD), the analysis was limited to an incremental cost per correct diagnosis. An analysis of NILTs to identify patients with cirrhosis for increased monitoring was also conducted.

RESULTS

Given a cost-effectiveness threshold of £20,000 per QALY, treating everyone with HCV without prior testing was cost-effective with an incremental cost-effectiveness ratio (ICER) of £9204. This was robust in most sensitivity analyses but sensitive to the extent of treatment benefit for patients with mild fibrosis. For HBV [hepatitis B e antigen (HBeAg)-negative)] this strategy had an ICER of £28,137, which was cost-effective only if the upper bound of the standard UK cost-effectiveness threshold range (£30,000) is acceptable. For HBeAg-positive disease, two NILTs applied sequentially (hyaluronic acid and magnetic resonance elastography) were cost-effective at a £20,000 threshold (ICER: £19,612); however, the results were highly uncertain, with several test strategies having similar expected outcomes and costs. For patients with ALD, liver biopsy was the cost-effective strategy, with an ICER of £822.

LIMITATIONS

A substantial number of tests had only one study from which diagnostic accuracy was derived; therefore, there is a high risk of bias. Most NILTs did not have validated cut-offs for diagnosis of specific fibrosis stages. The findings of the ALD model were dependent on assuptions about abstinence rates assumptions and the modelling approach for NAFLD was hindered by the lack of evidence on clinically effective treatments.

CONCLUSIONS

Treating everyone without NILTs is cost-effective for patients with HCV, but only for HBeAg-negative if the higher cost-effectiveness threshold is appropriate. For HBeAg-positive, two NILTs applied sequentially were cost-effective but highly uncertain. Further evidence for treatment effectiveness is required for ALD and NAFLD.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42011001561.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Hepatic Fibrosis Progression in HIV-Hepatitis C Virus Co-Infection--The Effect of Sex on Risk of Significant Fibrosis Measured by Aspartate-to-Platelet Ratio Index

BACKGROUND

In Hepatitis C virus (HCV) mono-infection, male sex is associated with faster liver fibrosis progression but the effects of sex have not been well studied in HIV-HCV co-infected patients. We examined the influence of sex on progression to significant liver fibrosis in HIV-HCV co-infected adults receiving antiretroviral therapy (ART) using the aspartate aminotransferase-to-platelet ratio index (APRI) as a surrogate biomarker of liver fibrosis.

METHODS

We evaluated 308 HIV infected, HCV RNA positive participants of a Canadian multicentre prospective cohort receiving antiretrovirals and without significant liver fibrosis or end-stage liver disease at baseline. We used multivariate discrete-time proportional hazards models to assess the effect of sex on time to significant fibrosis (APRI≥1.5) adjusting for baseline age, alcohol use, cigarette smoking, HCV duration, and APRI and time-updated CD4 count and HIV RNA.

RESULTS

Overall, 55 (18%) participants developed an APRI ≥ 1.5 over 544 person-years of at-risk follow-up time; 18 (21%) women (incidence rate (IR)=14.0/100 PY; 7.5-20.4) and 37 (17%) men (IR=8.9/100 PY; 6.0-11.8). Women had more favourable profiles with respect to traditional risk factors for liver disease progression (younger, shorter duration of HCV infection and less alcohol use). Despite this, female sex was associated with a greater than two-fold increased risk of fibrosis progression (adjusted hazard rate (HR) =2.23; 1.22-4.08).

CONCLUSIONS

HIV-HCV co-infected women receiving antiretroviral therapy were at significantly greater risk of progressing to liver fibrosis as measured by APRI compared with men. Enhanced efforts to engage and treat co-infected women for HCV are needed.

Highly active antiretroviral therapy-related hepatotoxicity in human immunodeficiency virus and hepatitis C virus co-infected patients with advanced liver fibrosis in Taiwan

BACKGROUND

The prevalence of patients co-infected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) is higher in Taiwan than in Western countries. This study aimed to analyze the frequency and risk factors for highly active antiretroviral therapy (HAART)-related liver toxicity in patients co-infected with HIV and HCV with advanced liver fibrosis in Taiwan.

METHODS

This retrospective cohort study included 228 HAART-experienced and HAART-naïve patients who were co-infected with HIV and HCV from January 2013 to December 2013 in Taiwan. Transaminase elevation (TE) was defined by grades. Fibrosis 4 score and aspartate-to-platelet ratio index were used to evaluate liver fibrosis. Cox proportional hazard regression model was used to analyze the risk factors for time to TE events.

RESULTS

A total of 228 patients were included. Only two episodes (1.28%) of high-grade TE were observed. The overall prevalence rate of TE was 16%, and the incidence was 1.38 cases/100 patient-months. Two predictive factors of TE were the initiation of HAART during the study period and CD4 cell count less than 350 cells/mm(3). Subgroup analysis showed that HAART improved liver fibrosis status in patients who had advanced liver fibrosis at baseline (p = 0.033).

CONCLUSION

The frequency of HAART-related TE in HIV and HCV co-infected patients in Taiwan was much lower than that observed in previous studies. Pre-existing advanced liver fibrosis had no influence on the frequency of TE. The use of HAART showed benefits on liver fibrosis progression in patients with underlying advanced liver fibrosis.

Prevalence and predictors of elevated aspartate aminotransferase-to-platelet ratio index in Latin American perinatally HIV-infected children

BACKGROUND

Chronic liver disease has emerged as an important problem in adults with longstanding HIV infection, but data are lacking for children. We characterized elevated aspartate aminotransferase-to-platelet ratio index (APRI), a marker of possible liver fibrosis, in perinatally HIV-infected children.

METHODS

The National Institute of Child Health and Human Development International Site Development Initiative enrolled HIV-infected children (ages 0.1-20.1 years) from 5 Latin American countries in an observational cohort from 2002 to 2009. Twice yearly visits included medical history, physical examination and laboratory evaluations. The prevalence (95% confidence interval) of APRI > 1.5 was calculated, and associations with demographic, HIV-related and liver-related variables were investigated in bivariate analyses.

RESULTS

APRI was available for 1012 of 1032 children. APRI was >1.5 in 32 (3.2%, 95% confidence interval: 2.2%-4.4%) including 2 of 4 participants with hepatitis B virus infection. Factors significantly associated with APRI > 1.5 (P < 0.01 compared with APRI ≤ 1.5) included country, younger age, past or current hepatitis B virus, higher alanine aminotransferase, lower total cholesterol, higher log10 current viral load, lower current CD4 count, lower nadir CD4 count, use of hepatotoxic nonantiretroviral (ARV) medications and no prior ARV use. Rates of APRI > 1.5 varied significantly by current ARV regimen (P = 0.0002), from 8.0% for no ARV to 3.2% for non-protease inhibitor regimens to 1.5% for protease inhibitor-based regimens.

CONCLUSIONS

Elevated APRI occurred in approximately 3% of perinatally HIV-infected children. Protease inhibitor-based ARVs appeared protective whereas inadequate HIV control appeared to increase risk of elevated APRI. Additional investigations are needed to better assess potential subclinical, chronic liver disease in HIV-infected children.

Elevated aspartate aminotransferase-to-platelet ratio index in perinatally HIV-infected children in the United States

Elevated aspartate aminotransferase-to-platelet ratio index may signal liver fibrosis. Among 397 US children with perinatal HIV infection, at baseline was >1.5 in 0.8% [95% confidence interval (CI), 0.2-2.2%) and >0.5 in 6.5% (95% CI, 4.3-9.4%); incidence on study was 0.5 (95% CI, 0.2-1.2) and 6.4 (95% CI, 4.8-8.3) per 100 person-years, respectively. Long-term liver outcomes after perinatal HIV infection warrant further study.

CD127 expression, exhaustion status and antigen specific proliferation predict sustained virologic response to IFN in HCV/HIV co-infected individuals

Hepatitis C virus (HCV) infection is a major cause of morbidity and mortality in the HIV co-infected population. Interferon-alpha (IFN-α) remains a major component of anti-HCV therapy despite its deleterious effects on the immune system. Furthermore, IFN-α was recently shown to diminish the size of the latent HIV reservoir. The objectives of this study were to monitor the impact of IFN-α on T cell phenotype and proliferation of HIV and HCV-specific T cells during IFN therapy, and to identify immune markers that can predict the response to IFN in HICV/HIV co-infected patients. We performed longitudinal analyses of T cell numbers, phenotype and function in co-infected patients undergoing IFN-α therapy with different outcomes including IFN-α non-responders (NR) (n = 9) and patients who achieved sustained virologic response (SVR) (n = 19). We examined the expression of activation (CD38, HLA-DR), functional (CD127) and exhaustion markers (PD1, Tim-3, CD160 and CD244) on total CD4 and CD8 T cells before, during and after therapy. In addition, we examined the HIV- and HCV-specific proliferative responses against HIV-p24 and HCV-NS3 proteins. Frequencies of CD127⁺ CD4 T cells were higher in SVR than in NR patients at baseline. An increase in CD127 expression on CD8 T cells was observed after IFN-α therapy in all patients. In addition, CD8 T cells from NR patients expressed a higher exhaustion status at baseline. Finally, SVR patients exhibited higher proliferative response against both HIV and HCV antigens at baseline. Altogether, SVR correlated with higher expression of CD127, lower T cell exhaustion status and better HIV and HCV proliferative responses at baseline. Such factors might be used as non-invasive methods to predict the success of IFN–based therapies in co-infected individuals.

HIV virological rebounds but not blips predict liver fibrosis progression in antiretroviral-treated HIV/hepatitis C virus-coinfected patients

OBJECTIVES

Antiretroviral interruption is associated with liver fibrosis progression in HIV/hepatitis C virus (HCV) coinfection. It is not known what level of HIV viraemia affects fibrosis progression.

METHODS

We evaluated 288 HIV/HCV-coinfected cohort participants with undetectable HIV RNA (<50 HIV-1 RNA copies/mL) on two consecutive visits while on combination antiretroviral therapy (cART) without fibrosis [aspartate aminotransferase to platelet ratio index (APRI) <1.5], end-stage liver disease or HCV therapy. An HIV blip was defined as a viral load of ≥ 50 and <1000 copies/mL, preceded and followed by undetectable values. HIV rebound was defined as: (i) HIV RNA ≥ 50 copies/mL on two consecutive visits, or (ii) a single HIV RNA measurement ≥ 1000 copies/mL. Multivariate discrete-time proportional hazards models were used to assess the effect of different viraemia levels on liver fibrosis progression (APRI ≥ 1.5).

RESULTS

The mean age of the patients was 45 years, 74% were male, 81% reported a history of injecting drug use, 51% currently used alcohol and the median baseline CD4 count was 440 [interquartile range (IQR) 298, 609] cells/μL. Fifty-seven (20%) participants [12.4/100 person-years (PY); 95% confidence interval (CI) 9.2-15.7/100 PY] progressed to an APRI ≥ 1.5 over a mean 1.1 (IQR 0.6, 2.0) years of follow-up time at risk. Virological rebound [hazard ratio (HR) 2.3; 95% CI 1.1, 4.7] but not blips (HR 0.5; 95% CI 0.2, 1.1) predicted progression to APRI ≥ 1.5. Each additional 1 log10 copies/mL HIV RNA exposure (cumulative) was associated with a 20% increase in the risk of fibrosis progression (HR 1.2; 95% CI 1.0-1.3).

CONCLUSIONS

Liver fibrosis progression was associated with HIV rebound, but not blips, and with increasing cumulative exposure to HIV RNA, highlighting the importance of achieving and maintaining HIV suppression in the setting of HIV/HCV coinfection.

Non-invasive diagnosis of liver fibrosis in chronic hepatitis C

Assessment of liver fibrosis in chronic hepatitis C virus (HCV) infection is considered a relevant part of patient care and key for decision making. Although liver biopsy has been considered the gold standard for staging liver fibrosis, it is an invasive technique and subject to sampling errors and significant intra- and inter-observer variability. Over the last decade, several noninvasive markers were proposed for liver fibrosis diagnosis in chronic HCV infection, with variable performance. Besides the clear advantage of being noninvasive, a more objective interpretation of test results may overcome the mentioned intra- and inter-observer variability of liver biopsy. In addition, these tests can theoretically offer a more accurate view of fibrogenic events occurring in the entire liver with the advantage of providing frequent fibrosis evaluation without additional risk. However, in general, these tests show low accuracy in discriminating between intermediate stages of fibrosis and may be influenced by several hepatic and extra-hepatic conditions. These methods are either serum markers (usually combined in a mathematical model) or imaging modalities that can be used separately or combined in algorithms to improve accuracy. In this review we will discuss the different noninvasive methods that are currently available for the evaluation of liver fibrosis in chronic hepatitis C, their advantages, limitations and application in clinical practice.

Relationship between alcohol use categories and noninvasive markers of advanced hepatic fibrosis in HIV-infected, chronic hepatitis C virus-infected, and uninfected patients

BACKGROUND

It is unclear if the risk of liver disease associated with different levels of alcohol consumption is higher for patients infected with human immunodeficiency virus (HIV) or chronic hepatitis C virus (HCV). We evaluated associations between alcohol use categories and advanced hepatic fibrosis, by HIV and chronic HCV status.

METHODS

We performed a cross-sectional study among participants in the Veterans Aging Cohort Study who reported alcohol consumption at enrollment (701 HIV/HCV-coinfected; 1410 HIV-monoinfected; 296 HCV-monoinfected; 1158 HIV/HCV-uninfected). Alcohol use category was determined by the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C) questionnaire and alcohol-related diagnoses and was classified as nonhazardous drinking, hazardous/binge drinking, or alcohol-related diagnosis. Advanced hepatic fibrosis was defined by FIB-4 index >3.25.

RESULTS

Within each HIV/HCV group, the prevalence of advanced hepatic fibrosis increased as alcohol use category increased. For each alcohol use category, advanced hepatic fibrosis was more common among HIV-infected than uninfected (nonhazardous: 6.7% vs 1.4%; hazardous/binge: 9.5% vs 3.0%; alcohol-related diagnosis: 19.0% vs 8.6%; P < .01) and chronic HCV-infected than uninfected (nonhazardous: 13.6% vs 2.5%; hazardous/binge: 18.2% vs 3.1%; alcohol-related diagnosis: 22.1% vs 6.5%; P < .01) participants. Strong associations with advanced hepatic fibrosis (adjusted odds ratio [95% confidence interval]) were observed among HIV/HCV-coinfected patients with nonhazardous drinking (14.2 [5.91-34.0]), hazardous/binge drinking (18.9 [7.98-44.8]), and alcohol-related diagnoses (25.2 [10.6-59.7]) compared with uninfected nonhazardous drinkers.

CONCLUSIONS

Advanced hepatic fibrosis was present at low levels of alcohol consumption, increased with higher alcohol use categories, and was more prevalent among HIV-infected and chronic HCV-infected patients than uninfected individuals. All alcohol use categories were strongly associated with advanced hepatic fibrosis in HIV/HCV-coinfected patients.

Prevalence and predictors of elevated aspartate aminotransferase-to-platelet ratio index in Latin American perinatally HIV-infected children

BACKGROUND

Chronic liver disease has emerged as an important problem in adults with longstanding HIV infection, but data are lacking for children. We characterized elevated aspartate aminotransferase-to-platelet ratio index (APRI), a marker of possible liver fibrosis, in perinatally HIV-infected children.

METHODS

The National Institute of Child Health and Human Development International Site Development Initiative enrolled HIV-infected children (ages 0.1-20.1 years) from 5 Latin American countries in an observational cohort from 2002 to 2009. Twice yearly visits included medical history, physical examination and laboratory evaluations. The prevalence (95% confidence interval) of APRI > 1.5 was calculated, and associations with demographic, HIV-related and liver-related variables were investigated in bivariate analyses.

RESULTS

APRI was available for 1012 of 1032 children. APRI was >1.5 in 32 (3.2%, 95% confidence interval: 2.2%-4.4%) including 2 of 4 participants with hepatitis B virus infection. Factors significantly associated with APRI > 1.5 (P < 0.01 compared with APRI ≤ 1.5) included country, younger age, past or current hepatitis B virus, higher alanine aminotransferase, lower total cholesterol, higher log10 current viral load, lower current CD4 count, lower nadir CD4 count, use of hepatotoxic nonantiretroviral (ARV) medications and no prior ARV use. Rates of APRI > 1.5 varied significantly by current ARV regimen (P = 0.0002), from 8.0% for no ARV to 3.2% for non-protease inhibitor regimens to 1.5% for protease inhibitor-based regimens.

CONCLUSIONS

Elevated APRI occurred in approximately 3% of perinatally HIV-infected children. Protease inhibitor-based ARVs appeared protective whereas inadequate HIV control appeared to increase risk of elevated APRI. Additional investigations are needed to better assess potential subclinical, chronic liver disease in HIV-infected children.

Hepatitis C co-infection and severity of liver disease as risk factors for osteoporotic fractures among HIV-infected patients

Osteoporosis is increasingly reported in the aging HIV-positive population, and co-infection with hepatitis C virus (HCV) may further increase the risk of osteoporosis. However, it remains unclear whether HCV-related increased fracture risk is a function of the severity of liver disease. We calculated the time-updated alanine aminotransferase to platelet ratio index (APRI) score (an indirect marker of hepatic fibrosis) in all HIV-infected patients enrolled in the Veterans Affairs' Clinical Case Registry between 1984 and 2009. The association between HCV co-infection and incident osteoporotic fracture (defined as closed wrist, vertebral, or hip fracture) was assessed in univariate and multivariate Cox survival models adjusting for traditional risk factors for osteoporosis and APRI score or the presence of cirrhosis. A total of 772 osteoporotic fractures were identified among 56,660 HIV-infected patients (98.1% male; 31.3% HCV co-infected; median age 44.0 years) contributing 305,237 patient-years of follow-up. Fracture rates were significantly higher among HIV/HCV patients than HIV-only patients (2.57 versus 2.07/1000 patient-years, relative risk = 1.24, p < 0.0001). In a Cox multivariable model including age, race, smoking, drug use, body mass index, and antiretroviral therapy, HCV co-infection remained an independent predictor of osteoporotic fractures after controlling for presence of cirrhosis (hazard ratio [HR] = 1.32; p <0.001) or APRI score (HR = 1.30; p = 0.003). Among HIV/HCV co-infected patients, cirrhosis strongly predicted osteoporotic fractures (HR = 1.65; 95% confidence interval [CI] 1.11-2.44; p = 0.012), but APRI score was a weaker predictor (HR = 1.008; 95% CI 1.002-1.014; p = 0.015). In conclusion, among HIV-infected patients, severity of liver disease partly explains the HCV-associated increased risk of osteoporotic fractures. Other determinants of this increased risk remain to be defined.

Non-invasive fibrosis biomarkers - APRI and Forns - are associated with liver stiffness in HIV-monoinfected patients receiving antiretroviral drugs

BACKGROUND & AIMS

HIV-monoinfected patients are susceptible to liver injury by different factors and may develop liver fibrosis, which requires adequate clinical management in terms of therapy and disease monitoring. We aimed to evaluate the presence of liver fibrosis identified by transient elastography (TE), its relationships with indirect biochemical markers [the aspartate aminotransferase/platelet ratio index (APRI), the Forns index and FIB-4] and its predictive factors in HIV-monoinfected patients receiving antiretroviral therapy (ART).

METHODS

Seventy-two HIV-monoinfected patients underwent TE and were evaluated using APRI, Forns and FIB-4. The clinical, immunological, virological and other biochemical characteristics were evaluated at the time of TE, together with their history of ART.

RESULTS

Seven patients (10%) had liver stiffness (LS) values predicting cirrhosis, and 12 (17%) had values predicting significant or advanced fibrosis. Higher indirect biochemical scores of liver fibrosis were significantly associated with higher LS values [APRI rs  = 0.4296 (P < 0.001); Forns rs  = 0.4754 (P < 0.001); FIB-4 rs  = 0.285 (P = 0.015)]. At multivariable analysis, APRI (β = 2.7405; P = 0.036), Forns (β = 1.4174; P = 0.029) and triglyceride levels (β = 1.3028; P = 0.007) were independently associated with LS.

CONCLUSIONS

Indirect fibrosis biomarkers may increase the probability to detect liver injury enhancing a specific diagnostic workup and so contribute to improving the clinical management of HIV-monoinfected patients with clinically suspected liver disease.

Staging of liver disease: which option is right for my patient?

It is important to assess the stage of liver fibrosis in chronic hepatitis C to guide treatment decisions. Liver biopsy has limitations in staging fibrosis. Several blood tests, algorithms, and imaging tests have been studied as noninvasive markers to stage fibrosis in hepatitis C. In patients without suspicion for cirrhosis, 2 noninvasive methods can be used to predict presence of absence of significant liver fibrosis; however, liver biopsy remains the gold standard. It is imperative not to miss the diagnosis of cirrhosis, because this has further implications for screening of hepatocellular carcinoma and varices.

CIHR Canadian HIV Trials Network Coinfection and Concurrent Diseases Core: Canadian guidelines for management and treatment of HIV/hepatitis C coinfection in adults

BACKGROUND

Hepatitis C virus (HCV) coinfection occurs in 20% to 30% of Canadians living with HIV, and is responsible for a heavy burden of morbidity and mortality. HIV-HCV management is more complex due to the accelerated progression of liver disease, the timing and nature of antiretroviral and HCV therapy, mental health and addictions management, socioeconomic obstacles and drug-drug interactions between new HCV direct-acting antiviral therapies and antiretroviral regimens.

OBJECTIVE

To develop national standards for the management of HCV-HIV coinfected adults in the Canadian context.

METHODS

A panel with specific clinical expertise in HIV-HCV co-infection was convened by The CIHR HIV Trials Network to review current literature, existing guidelines and protocols. Following broad solicitation for input, consensus recommendations were approved by the working group, and were characterized using a Class (benefit verses harm) and Level (strength of certainty) quality-of-evidence scale.

RESULTS

All HIV-HCV coinfected individuals should be assessed for HCV therapy. Individuals unable to initiate HCV therapy should initiate antiretroviral therapy to slow liver disease progression. Standard of care for genotype 1 is pegylated interferon and weight-based ribavirin dosing plus an HCV protease inhibitor; traditional dual therapy for 24 weeks (for genotype 2/3 with virological clearance at week 4); or 48 weeks (for genotypes 2-6). Therapy deferral for individuals with mild liver disease may be considered. HIV should not be considered a barrier to liver transplantation in coinfected patients.

DISCUSSION

Recommendations may not supersede individual clinical judgement.

Insulin resistance is associated with progression to hepatic fibrosis in a cohort of HIV/hepatitis C virus-coinfected patients

OBJECTIVE

Hepatitis C virus (HCV) infection is associated with higher insulin levels and insulin resistance. We evaluated factors associated with insulin resistance in a cohort of HIV/HCV-coinfected patients and determined the effect of insulin resistance on the development of hepatic fibrosis.

METHODS

Data were analysed from 158 nondiabetic participants in a prospective Canadian cohort of HIV/HCV-coinfected patients. Patients were defined as having insulin resistance using the homeostasis model for assessment of insulin resistance (HOMA-IR) index. Factors associated with a high index (HOMA-IR ≥ 2) were identified using multivariate logistic regression. Incidence rates of liver fibrosis [aspartate aminotransferase- to-platelet ratio index (APRI) ≥ 1.5] were calculated, and multivariate time-dependent Cox regression models used to assess the effect of baseline insulin resistance on the risk of developing an APRI score of at least 1.5 during follow-up.

RESULTS

Overall, 56% had baseline HOMA-IR of at least 2. In the adjusted multivariate logistic analysis, only baseline BMI of more than 25 kg/m2 remained associated with insulin resistance [adjusted odds ratio 3.66, 95% confidence interval (CI) 1.70-7.92]. Rates of progression to significant hepatic fibrosis (APRI ≥ 1.5) were higher in those with HOMA-IR of at least 2 (16.32 per 100 person-years, 95% CI 6.68-25.97) compared with those with HOMA-IR less than 2 (7.95 per 100 person-years, 95% CI 0.16-15.75). Baseline HOMA-IR of at least 2 was associated with the development of significant fibrosis (adjusted hazard ratio 7.71, 95% CI 2.55-23.36).

Clinical and virological characteristics of hepatitis B or C virus co-infection with HIV in Indonesian patients

Hepatitis virus-related liver disease increases substantially the mortality rate of patients with HIV on highly active antiretroviral therapy (HAART). Therefore, early diagnosis of hepatitis B virus (HBV) and hepatitis C virus (HCV) is important. However, the prevalence of HBV and HCV infection in Indonesian patients infected with HIV is unknown. Therefore, this study examined the molecular and clinical characteristics of HBV and HCV in 126 patients infected with HIV, mostly on HAART, at Dr. Sardjito Hospital, Yogyakarta, Indonesia. The rates of triple infection, HIV/HCV co-infection, HIV/HBV co-infection, and mono-infection were 4.8%, 34.1%, 3.2%, and 57.9%, respectively. Seven HCV genotypes were detected, with genotypes 1a, 1b, 1c, 3a, 3k, 4a, and 6n found in 23 (52%), 1 (2%), 4 (9%), 5 (11%), 7 (16%), 3 (6%), and 1 (2%) patients, respectively, indicating multiple modes of transmission. HBV-DNA was detected in 2/10 patients with hepatitis B surface antigen; both patients were HAART naive. Univariate analysis revealed that male sex, higher education level, injection drug use, sexual contact, alanine aminotransferase ≥40 IU/L, and aspartate aminotransferase-to-platelet ratio index > 0.5 were associated with HCV co-infection. In multivariate analysis, injection drug use (OR: 26.52; 95% CI: 3.52-199.54) and alanine aminotransferase ≥40 IU/L (OR: 6.36; 95% CI: 1.23-32.89) were independently associated with HCV co-infection. HCV co-infection was common among Indonesian patients infected with HIV, particularly among injecting drug users, and was a risk factor for disease progression of HIV.

HIV and hepatitis C virus coinfection in Canada: challenges and opportunities for reducing preventable morbidity and mortality

OBJECTIVES

Hepatitis C virus (HCV) has emerged as an important health problem in the era of effective HIV treatment. However, very few data exist on the health status and disease burden of HIV/HCV-coinfected Canadians.

METHODS

HIV/HCV-coinfected patients were enrolled prospectively in a multicentre cohort from 16 centres across Canada between 2003 and 2010 and followed every 6 months. We determined rates of a first liver fibrosis or endstage liver disease (ESLD) event and all-cause mortality since cohort enrolment and calculated standardized mortality ratios compared with the general Canadian population.

RESULTS

A total of 955 participants were enrolled in the study and followed for a median of 1.4 (interquartile range 0.5-2.3) years. Most were male (73%) with a median age of 44.5 years; 13% self-identified as aboriginal. There were high levels of current injecting drug and alcohol use and poverty. Observed event rates [per 100 person-years; 95% confidence interval (CI)] were: significant fibrosis (10.21; 8.49, 12.19), ESLD (3.16; 2.32, 4.20) and death (3.72; 2.86, 4.77). The overall standardized mortality ratio was 17.08 (95% CI 12.83, 21.34); 12.80 (95% CI 9.10, 16.50) for male patients and 28.74 (95% CI 14.66, 42.83) for female patients. The primary causes of death were ESLD (29%) and overdose (24%).

CONCLUSIONS

We observed excessive morbidity and mortality in this HIV/HCV-coinfected population in care. Over 50% of observed deaths may have been preventable. Interventions aimed at improving social circumstances, reducing harm from drug and alcohol use and increasing the delivery of HCV treatment in particular will be necessary to reduce adverse health outcomes among HIV/HCV-coinfected persons.

Factors associated with discordance between absolute CD4 cell count and CD4 cell percentage in patients coinfected with HIV and hepatitis C virus

BACKGROUND

Liver cirrhosis has been associated with decreased absolute CD4 cell counts but preserved CD4 cell percentage in human immunodeficiency virus (HIV)-negative persons. We evaluated factors associated with discordance between the absolute CD4 cell count and the CD4 cell percentage in a cohort of patients coinfected with HIV and hepatitis C virus (HCV).

METHODS

Baseline data from 908 participants in a prospective, Canadian, multisite cohort of individuals with HIV-HCV coinfection were analyzed. Absolute CD4 cell count and CD4 cell percentage relationships were evaluated. We defined low and high discordance between absolute CD4 cell count/CD4 cell percentage relationships as CD4 cell percentages that differed from the expected CD4 cell percentage, given the observed absolute CD4 cell count, by ±7 percentage points; we defined very low and very high discordance as differences of ±14 percentage points. Factors associated with high or very high discordance, including either end-stage liver disease or aspartate transaminase to platelet ratio index (APRI) of >1.5, were analyzed using multivariate logistic regression models and compared to groups with concordant and low discordant results.

RESULTS

High/very high discordance was seen in 31% (n = 286), while 35% (n = 321) had concordant values. Factors associated with very high discordance at baseline included history of end-stage liver disease (adjusted odds ratio [aOR], 6.52; 95% confidence interval [CI], 2.27-18.67) and APRI of >1.5 (aOR 4.69; 95% CI, 1.64-13.35). Compared with those with detectable HCV RNA, those who cleared HCV spontaneously were less likely to have very high discordance.

CONCLUSIONS

Discordance between absolute CD4 cell count and CD4 cell percentage is common in an HIV/HCV-coinfected population and is associated with advanced liver disease and ongoing HCV replication.

Assessment of liver disease (noninvasive methods)

PURPOSE OF REVIEW

The purpose of this review is to highlight new findings published in 2010-2011 related to noninvasive fibrosis assessment in HIV/hepatitis C virus (HCV) co-infected patients. Overall, in 2010-2011, 15 studies were published, of which two were excluded because they were published in languages other than English.

RECENT FINDINGS

Eleven studies focused on serum marker panels. Studies sought to validate established panels in HIV/HCV co-infected patients often by comparing multiple serum marker panels in the same population; establish new marker panels using combinations of markers used in previously validated panels; and develop new marker panels using novel methodology. Overall, all panels performed within similar ranges of diagnostic accuracy as measured by the area under the receiver operating characteristic curve (AUROC) but the FibroMeter panel and its derivations achieved the highest performance. Four studies focused on transient elastography. Two studies confirmed its accuracy for identifying fibrosis and cirrhosis and two studies confirmed that misclassification rates are higher in the presence of elevated triglycerides and steatosis.

SUMMARY

Overall, performance of transient elastography appeared superior to the majority of serum marker panels for the detection of significant fibrosis and cirrhosis in HIV/HCV co-infected patients. Challenges of widespread application of transient elastography remain high misclassification in some subgroups, lack of standardized cut-points and lack of widespread availability. Panels that were newly developed in 2010-2011 specifically for HIV/HCV appeared to perform better than existing panels such as APRI and FIB-4; however, additional external validation will be needed to confirm their accuracy.

Effects of Angiotensin Converting Enzyme Inhibitors on Liver Fibrosis in HIV and Hepatitis C Coinfection

Background. Liver fibrosis is accelerated in HIV and hepatitis C coinfection, mediated by profibrotic effects of angiotensin. The objective of this study was to determine if angiotensin converting enzyme inhibitors (ACE-Is) attenuate liver fibrosis in coinfection. Methods. A retrospective review of 156 coinfected subjects was conducted to analyze the association between exposure to ACE-Is and liver fibrosis. Noninvasive indices of liver fibrosis (APRI, FIB-4, Forns indices) were compared between subjects who had taken ACE-Is and controls who had not taken them. Linear regression was used to evaluate ACE-I use as an independent predictor of fibrosis. Results. Subjects taking ACE-Is for three years were no different than controls on the APRI and the FIB-4 but had significantly higher scores than controls on the Forns index, indicating more advanced fibrosis. The use of ACE-Is for three years remained independently associated with an elevated Forns score when adjusted for age, race, and HIV viral load (P < 0.001). There were significant associations between all of the indices and significant fibrosis, as determined clinically and radiologically. Conclusions. There was not a protective association between angiotensin inhibition and liver fibrosis in coinfection. These noninvasive indices may be useful for ruling out significant fibrosis in coinfection.

[Treatment of hepatitis C virus in HIV-positive patients]

Hepatitis C virus (HCV)-HIV coinfection currently occurs in more than 30% of HIV-positive patients in Spain. Nowadays, the treatment of choice for chronic hepatitis due to HCV infection in HIV-positive patients is pegylated interferon plus ribavirin. This combination achieves an overall cure rate of 50%, which is somewhat lower than those obtained in patients with HCV monoinfection. Adverse effects are frequent, leading to treatment withdrawal in 10-20% of patients. Importantly, there are three new features of hepatitis C in patients with HIV: (1) the recent development of epidemic outbreaks of acute hepatitis due to HCV infection in HIV-positive men caused by homosexual activity, (2) pharmacogenetic markers in the form of genetic polymorphisms near the IL28B gene related to response to HCV treatment as well as spontaneous eradication of HCV after acute infection, and (3) new antiviral molecules have allowed triple combination treatments to be designed and the preliminary results of clinical trials reporting high response rates are highly promising.

Management of HIV and hepatitis virus coinfection

IMPORTANCE OF THE FIELD

Liver disease related to infection with hepatitis C virus (HCV) and/or hepatitis B virus (HBV) is a frequent cause of morbidity and mortality in those infected with the human immunodeficiency virus (HIV) in this era of highly active antiretroviral therapy (HAART). Although progress has been made in the treatment of HBV and HCV in the setting of HIV-coinfection, there is a lack of data in certain areas and several aspects of the management are unclear at this time.

AREAS COVERED IN THIS REVIEW

Available data on the treatment of HBV and HCV infections, especially in the HIV-coinfected patient, are presented. Practical aspects of the management of these patients are reviewed, including diagnosis, treatment indications, monitoring, and toxicities. The impact of HAART on liver disease, end-stage-liver disease, and new therapeutic approaches are also reviewed.

WHAT THE READER WILL GAIN

There are two modalities for the treatment of chronic HBV infection: interferon and nucleos(t)ide reverse transcriptase inhibitors (NRTI). The latter is the mainstream of therapy for HIV-HBV-coinfected patients. The double antiviral activity of NRTI requires coordination and careful selection of treatment for both viruses to avoid selection of resistance mutations and toxicity. Combination of pegylated interferon and ribavirin, the current standard treatment for chronic hepatitis C, has significant toxicity and limited efficacy in HIV-HCV-coinfected individuals. Oral anti-HCV treatments are currently under development and need to be studied in the HIV-coinfected population. Liver transplantation has a better outcome in HBV- than in HCV-HIV-coinfected patients. HAART seems to have a positive impact on the liver disease of HBV- and/or HCV-coinfected subjects but the CD4 threshold above which the benefit might take place is unknown at this time.

TAKE HOME MESSAGE

Anti-HBV treatment in the HIV-coinfected patient relies on the available NRTIs with activity against both viruses. Whereas HBV suppression can be achieved with this approach, toxicities and the selection of HBV-resistant variants result in challenging clinical scenarios. Current anti-HCV treatment (pegylated interferon and ribavirin) has limited efficacy in the HIV-coinfected patient, and STAT-C drugs are eagerly awaited.

Antiretroviral treatment interruption leads to progression of liver fibrosis in HIV-hepatitis C virus co-infection

OBJECTIVE

Despite potential negative consequences, HIV/hepatitis C virus (HCV) co-infected patients may discontinue antiretroviral treatment (ART) for several reasons. We examined the impact of ART interruption on liver fibrosis progression in co-infected adults, using the aspartate aminotransferase-to-platelet ratio index (APRI) as a surrogate marker of liver fibrosis.

METHOD

Data were analyzed from a multisite prospective cohort of 541 HIV-HCV co-infected adults. ART interruption was included as a time-updated variable and defined as the cessation of all antiretrovirals for at least 14 days. The primary endpoint was the development of an APRI score at least 1.5. Time-dependent Cox proportional hazards regression and inverse probability-of-treatment weighting (IPTW) in a marginal structural model were used to evaluate the association of baseline and time-varying covariates with developing significant fibrosis.

RESULTS

Patients were followed for a median of 1.02 years; 10% (n = 53) interrupted ART and 10% (n = 53) developed significant fibrosis. After accounting for potential confounders, including CD4 T-cell count, HIV viral load, baseline APRI score, age and gender, the hazard ratio for ART interruption was 2.52 (95% confidence interval 1.20-5.28). Use of IPTW resulted in a similar effect estimate, suggesting that mediation by time-varying confounders was negligible.

CONCLUSION

ART interruption was associated with an increased risk of fibrosis progression in HIV-HCV co-infection that was only partially accounted for by HIV viral load and CD4 T-cell counts. Our findings suggest that liver disease progression observed in ART-treated co-infected patients is partly due to the consequences of treatment interruptions.

Performance of the aspartate aminotransferase-to-platelet ratio index for the staging of hepatitis C-related fibrosis: an updated meta-analysis

The aspartate aminotransferase-to-platelet ratio index (APRI), a tool with limited expense and widespread availability, is a promising noninvasive alternative to liver biopsy for detecting hepatic fibrosis. The objective of this study was to update the 2007 meta-analysis to systematically assess the accuracy of APRI in predicting significant fibrosis, severe fibrosis, and cirrhosis stage in hepatitis C virus (HCV) monoinfected and HCV / human immunodeficiency virus (HIV) coinfected individuals. Studies comparing APRI versus biopsy in HCV patients were identified via a thorough literature search. Areas under summary receiver operating characteristic curves (AUROC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were used to examine the APRI accuracy for the diagnosis of significant fibrosis, severe fibrosis, and cirrhosis. Heterogeneity was explored using meta-regression. Twenty-one additional studies were eligible for the update and, in total, 40 studies were included in this review (n = 8,739). The summary AUROC of the APRI for the diagnosis of significant fibrosis, severe fibrosis, and cirrhosis were 0.77, 0.80, and 0.83, respectively. For significant fibrosis, an APRI threshold of 0.7 was 77% sensitive and 72% specific. For severe fibrosis, a threshold of 1.0 was 61% sensitive and 64% specific. For cirrhosis, a threshold of 1.0 was 76% sensitive and 72% specific. Moreover, we found that the APRI was less accurate for the identification of significant fibrosis, severe fibrosis, and cirrhosis in HIV/HCV coinfected patients.

CONCLUSION

Our large meta-analysis suggests that APRI can identify hepatitis C-related fibrosis with a moderate degree of accuracy. Application of this index may decrease the need for staging liver biopsy specimens among chronic hepatitis C patients.

Use of the AST to platelet ratio index in HCV/HIV co-infected patients

BACKGROUND

The AST to platelet ratio index (APRI), a non-invasive marker of liver fibrosis, has not been well studied in HCV/HIV (hepatitis C virus/human immunodeficiency virus) co-infected patients with advanced HIV.

AIM

To compare the accuracy of APRI in HCV/HIV co-infected patients to that in HCV mono-infected patients and to determine the impact of CD4+ T-cell counts on its performance.

METHODS

We identified 106 consecutive HCV/HIV co-infected patients and 105 matched HCV mono-infected patients who underwent liver biopsy at Harborview Medical Center over a 5-year period. Performance characteristics were calculated and receiver operating characteristic (ROC) analysis conducted.

RESULTS

The area under the ROC curve (AUROC) of APRI for predicting significant fibrosis was similar when comparing those with and without HIV co-infection (0.77 vs. 0.86, P = 0.18), but was lower in HIV co-infected patients with CD4 counts <250 cells/mm³ (0.64 vs. 0.86, P = 0.05). In HIV co-infected patients with CD4 counts ≥250, APRI had higher negative predictive value (93% vs. 88%, P = 0.57), positive predictive value (63% vs. 40%, P = 0.43) and specificity (95% vs. 88%, P = 0.05) than in those with lower CD4 counts.

CONCLUSIONS

The AST to platelet ratio index (APRI) performance characteristics appear to be suboptimal in HCV/HIV co-infected patients with CD4 counts <250 and they require further study in this population at increased risk for advanced liver disease.

HCV-specific T cells in HCV/HIV co-infection show elevated frequencies of dual Tim-3/PD-1 expression that correlate with liver disease progression

Co-infection of HCV with HIV has been associated with more rapid progression of HCV-related disease. HCV-specific T-cell immune responses, which are essential for disease control, are attenuated in co-infection with HIV. T-cell exhaustion has recently been implicated in the deficient control of chronic viral infections. In the current study, we investigated the role of programmed death-1 (PD-1) and T-cell immunoglobulin and mucin domain-containing molecule-3 (Tim-3) expression in T-cell exhaustion during HCV/HIV co-infection. We show that in HCV/HIV co-infection, both total and HCV-specific T cells co-express Tim-3 and PD-1 in significantly higher frequencies, compared with HCV mono-infection. Co-expression of these two markers on HCV-specific CD8(+) T cells positively correlated with a clinical parameter of liver disease progression. HCV-specific CD8(+) T cells showed greater frequencies of Tim-3/PD-1 co-expression than HIV-specific CD8(+) T cells, which may indicate a greater degree of exhaustion in the former. Blocking Tim-3 or PD-1 pathways restored both HIV- and HCV-specific CD8(+) T-cell expansion in the blood of co-infected individuals. These data demonstrate that co-expression of Tim-3 and PD-1 may play a significant role in HCV-specific T-cell dysfunction, especially in the setting of HIV co-infection.

Characterization of cross-reactive CD8+ T-cell recognition of HLA-A2-restricted HIV-Gag (SLYNTVATL) and HCV-NS5b (ALYDVVSKL) epitopes in individuals infected with human immunodeficiency and hepatitis C viruses

The immunologic mechanisms underlying the faster progression of hepatitis C virus (HCV) disease in the presence of human immunodeficiency virus (HIV) coinfection are not clearly understood. T-cell cross-reactivity between HCV and influenza virus-specific epitopes has been associated with rapid progression of HCV disease (S. Urbani, B. Amadei, P. Fisicaro, M. Pilli, G. Missale, A. Bertoletti, and C. Ferrari, J. Exp. Med. 201:675-680, 2005). We asked whether T-cell cross-reactivity between HCV and HIV could exist during HCV/HIV coinfection and affect pathogenesis. Our search for amino acid sequence homology between the HCV and HIV proteomes revealed two similar HLA-A2-restricted epitopes, HIV-Gag (SLYNTVATL [HIV-SL9]) and HCV-NS5b (ALYDVVSKL [HCV-AL9]). We found that 4 out of 20 HLA-A2-positive (HLA-A2(+)) HIV-infected individuals had CD8(+) T cells that recognized both the HIV-SL9 and HCV-AL9 epitopes. However, the AL9 epitope was generally shown to be a weak agonist. Although HCV-monoinfected individuals in our study did not show AL9-specific responses, we found that about half of HCV/HIV-coinfected individuals had dual responses to both epitopes. High dual T-cell recognition among coinfected subjects was usually due to separate T-cell populations targeting each epitope, as determined by pentamer staining. The one individual demonstrating cross-reactive T cells to both epitopes showed the most advanced degree of liver disease. In coinfected individuals, we observed a positive correlation between the magnitudes of T-cell responses to both the SL9 and the AL9 epitopes, which was also positively associated with the clinical parameter of liver damage. Thus, we find that HIV infection induces T cells that can cross-react to heterologous viruses or prime for T cells that are closely related in sequence. However, the induction of cross-reactive T cells may not be associated with control of disease caused by the heterologous virus. This demonstrates that degeneracy of HIV-specific T cells may play a role in the immunopathology of HCV/HIV coinfection.

Comparison of liver fibrosis blood tests developed for HCV with new specific tests in HIV/HCV co-infection

BACKGROUND & AIMS

We compared 5 non-specific and 2 specific blood tests for liver fibrosis in HCV/HIV co-infection.

METHODS

Four hundred and sixty-seven patients were included into derivation (n=183) or validation (n=284) populations. Within these populations, the diagnostic target, significant fibrosis (Metavir F > or = 2), was found in 66% and 72% of the patients, respectively. Two new fibrosis tests, FibroMeter HICV and HICV test, were constructed in the derivation population.

RESULTS

Unadjusted AUROCs in the derivation population were: APRI: 0.716, Fib-4: 0.722, Fibrotest: 0.778, Hepascore: 0.779, FibroMeter: 0.783, HICV test: 0.822, FibroMeter HICV: 0.828. AUROCs adjusted on classification and distribution of fibrosis stages in a reference population showed similar values in both populations. FibroMeter, FibroMeter HICV and HICV test had the highest correct classification rates in F0/1 and F3/4 (which account for high predictive values): 77-79% vs. 70-72% in the other tests (p=0.002). Reliable individual diagnosis based on predictive values > or = 90% distinguished three test categories: poorly reliable: Fib-4 (2.4% of patients), APRI (8.9%); moderately reliable: Fibrotest (25.4%), FibroMeter (26.6%), Hepascore (30.2%); acceptably reliable: HICV test (40.2%), FibroMeter HICV (45.6%) (p<10(-3) between tests). FibroMeter HICV classified all patients into four reliable diagnosis intervals (< or =F1, F1+/-1, > or =F1, > or =F2) with an overall accuracy of 93% vs. 79% (p<10(-3)) for a binary diagnosis of significant fibrosis.

CONCLUSIONS

Tests designed for HCV infections are less effective in HIV/HCV infections. A specific test, like FibroMeter HICV, was the most interesting test for diagnostic accuracy, correct classification profile, and a reliable diagnosis. With reliable diagnosis intervals, liver biopsy can therefore be avoided in all patients.

Assessment of liver fibrosis and cirrhosis by aspartate aminotransferase-to-platelet ratio index in children with biliary atresia

BACKGROUND

In patients with biliary atresia (BA), liver fibrosis and cirrhosis commonly occur even after Kasai hepatoportoenterostomy. Although liver biopsy is the gold standard to evaluate liver fibrosis, it is invasive and may result in life-threatening complications. The aspartate aminotransferase-to-platelet ratio index (APRI) is a safe and simple method to assess liver fibrosis in patients with chronic liver diseases. To use APRI as a postoperative follow-up tool, we validated the diagnostic power of APRI for the degree of liver fibrosis in postoperative patients with BA.

PATIENTS AND METHODS

Patients with newly diagnosed BA who underwent the Kasai procedure between March 2006 and May 2009 were analyzed. Several laboratory tests including APRI were performed. Liver wedge biopsy specimens were obtained during the surgical procedure, and histopathologic analyses were performed using the Metavir classification.

RESULTS

Thirty-five patients (12 boys, median age of 1.9 months) were enrolled. Metavir scores were F1 in 0, F2 in 11, F3 in 11, and F4 in 13 patients. The areas under the receiver operating characteristics curves for F > or = 3 and F = 4 were 0.92 and 0.91, respectively. Distinct optimal cutoff values of APRI for F > or = 3 and F = 4 were obtained (1.01 and 1.41, respectively). Clinical outcomes of patients were significantly different between 2 groups (noncirrhosis vs cirrhosis) based on APRI before and 3 months after the Kasai procedure.

CONCLUSION

APRI may be used as a simple and readily available tool for assessing liver fibrosis without additional risks in patients with BA during postoperative follow-up care.

Prevalence and risk factors for significant liver fibrosis among HIV-monoinfected patients

BACKGROUND

HIV-monoinfected patients may be at risk for significant liver fibrosis, but its prevalence and determinants in these patients are unknown. Since HIV-monoinfected patients do not routinely undergo liver biopsy, we evaluated the prevalence and risk factors of significant hepatic fibrosis in this group using the aspartate aminotransferase (AST)-to-platelet ratio index (APRI).

METHODS

We conducted a cross-sectional study among HIV-infected patients negative for hepatitis B surface antigen and hepatitis C antibody in the Penn Center for AIDS Research Adult/Adolescent Database. Clinical and laboratory data were collected from the database at enrollment. Hypothesized determinants of significant fibrosis were modifiable risk factors associated with liver disease progression, hepatic fibrosis, or hepatotoxicity, including immune dysfunction (i.e., CD4 T lymphocyte count <200 cells/mm(3), HIV viremia), diseases associated with hepatic steatosis (e.g., obesity, diabetes mellitus), and use of antiretroviral therapy. The primary outcome was an APRI score >1.5, which suggests significant hepatic fibrosis. Multivariable logistic regression identified independent risk factors for significant fibrosis by APRI.

RESULTS

Among 432 HIV-monoinfected patients enrolled in the CFAR Database between November 1999 and May 2008, significant fibrosis by APRI was identified in 36 (8.3%; 95% CI, 5.9-11.4%) patients. After controlling for all other hypothesized risk factors as well as active alcohol use and site, detectable HIV viremia (adjusted OR, 2.56; 95% CI, 1.02-8.87) and diabetes mellitus (adjusted OR, 3.15; 95% CI, 1.12-10.10) remained associated with significant fibrosis by APRI.

CONCLUSIONS

Significant fibrosis by APRI score was found in 8% of HIV-monoinfected patients. Detectable HIV viremia and diabetes mellitus were associated with significant fibrosis. Future studies should explore mechanisms for fibrosis in HIV-monoinfected patients.

Use of simple noninvasive biomarkers to predict liver fibrosis in HIV/HCV coinfection in routine clinical practice

BACKGROUND

Simple noninvasive tests to predict fibrosis, as an alternative to liver biopsy (LB), are needed. Of these, the aspartate aminotransferase (AST) to platelet ratio index (APRI) and the Forns index (FI) have been validated in HIV/hepatitis C virus (HCV) coinfection. However, these indexes may have lower diagnostic value in situations other than the circumscribed conditions of validation studies. We therefore examined the value of the APRI and FI in HIV/HCV-coinfected patients for the detection of significant fibrosis in real-life conditions.

PATIENTS AND METHODS

HIV/HCV-coinfected patients who had participated in a multicentre cross-sectional retrospective study were selected if they had undergone an LB within 24 months before the last visit. The predictive accuracy of the APRI and FI was measured using the areas under receiver-operating-characteristic curves (AUROCs). Diagnostic accuracy was determined using the positive (PPV) and negative (NPV) predictive values.

RESULTS

A total of 519 coinfected individuals were included in the study. The AUROC [95% confidence interval (95% CI)] of the APRI was 0.67 (0.66-0.71) and that of the FI was 0.67 (0.62-0.71). The PPV of the APRI was 79% and its NPV was 66%. The PPV of the FI was 74% and its NPV was 64%. LB length was available and was > or =15 mm in 120 individuals. In this group, the PPV of the APRI was 85%, and that of the FI was 81%. Using these indexes, 22% of patients could be spared LB. Applying both models sequentially, 30% of patients could be spared LB.

CONCLUSIONS

In HIV/HCV-coinfected patients, the diagnostic accuracy of the APRI in real-life conditions was similar to that in the validation studies. The FI performed less well. However, combining the two indexes to make decisions on anti-HCV therapy may prevent a significant proportion of patients from having to undergo LB.